1. Field of the Invention
The invention relates to an apparatus for producing a sleeve-type printing forme from a plate-like blank, including a housing, a feed table outside the housing for receiving a plate-like blank, a round shaping device in the housing for shaping a plate-like blank into a sleeve-type printing forme, a transport device which is moveable to transport the plate-like blank from the feed table to the round shaping device, and a laser cutting and welding system in the housing for laser cutting and laser welding the plate-like blank on the round shaping device after the blank has been formed into a sleeve.
2. Description of the Related Art
U.S. Pat. No. 5,557,960 discloses an apparatus of this type, which merely requires the plate-like blank to be inserted manually and, after the plate has been inserted, automatically permits the round shaping operation and the exact register-maintaining positioning of the ends of the plate to be joined or to be welded.
In order to avoid cutting the plate-like raw forme to length outside this apparatus by means of a sheet-metal shear, whilst maintaining the dimensions, it is proposed in U.S. Pat. No. 5,499,580 to improve the production operation of the sleeve-like printing forme in this apparatus by cutting the plate-like raw forme, having a width corresponding to the forme cylinder, to length roughly at a length that is greater than that defined for a printing forme. The raw forme in the in-register, rounded state is cut to length, maintaining its dimensions, in the welding apparatus by means of the laser beam as a cutting device, so that at least one piece of waste is produced. The piece of waste is removed, the two edges of the plate forming the start and end of the printing forme are set opposite each other with no overlap and are welded to each other.
U.S. Pat. No. 5,992,727 discloses a further generic apparatus. Here, above the feed table and in the housing which can be closed so as to be secure against radiation, an opening is left through which a device for fixing the plate-like blank as a planar raw forme, in the forme of a fixing frame that can be adjusted to the appropriate plate size, can be moved out of the housing over the feed table in order to pick up the raw forme.
The fixing frame comprises two holdfast strips which can be adjusted on a carriage in accordance with the distance between the edges of the plate of the raw forme to be joined and can be set longitudinally on the respective plate edge. The fixing frame further comprises a register device, which is designed such that it interacts with a register system on the plate-like raw forme. For example, the plate edges here can be fixed in-register to these holdfast strips by means of a pin register belonging to the holdfast strips arranged on the fixing frame and a register hole system belonging to the plate-like raw forme.
The disadvantage of the apparatus described above is that in order to produce the sleeve-like printing forme in register, operations are carried out with an external register hole system as a register device. However, this always requires the use of a plate punch by means of which the plate-like raw forme is provided with the register device in the form of the register hole system.
It is an object of the invention to provide an improved generic apparatus which ensures an in-register production operation of the sleeve-like printing forme, it being possible to dispense with a register arranged in the plate-like raw forme in the form of a register hole system.
According to the invention, the transport device includes a plate suction frame penetrated by suction elements for picking up a plate-like blank placed on the feed table in a fixed level position and transporting it in a stable position to the round shaping device so that the plate-like blank can be deposited on the round shaping device aligned level and fixed in register.
A significant advantage is that with the omission of the external register hole system in the plate-like raw forme, a plate punch can be dispensed with. The apparatus according to the invention permits an in-register production operation of a sleeve-like printing forme, less trim being produced when the raw forme is cut to length, maintaining its dimensions, in the in-register, rounded state.
It is significant that, by means of the fixing means configured as suction elements on the plate suction frame of the apparatus, both raw formes made of nonmagnetic material, for example aluminum, and raw formes made of magnetizable material can be fixed flat and aligned level and can be transported. The suction elements are advantageously arranged in a grid. The grid is configured in such a way that a large number of frequently occurring printing-forme diameters and printing-forme widths, which lie within the range of the minimum length and maximum length of the raw forme and therefore determine the extent of the sleeve-like printing forme, are covered. Furthermore, the suction elements are arranged in the grid in such a way that the raw forme, from which the printing-forme diameters and printing-forme widths normally used are produced, is gripped and conveyed by the plate suction frame or by the suction elements without sagging.
Furthermore, it is significant that, by means of the apparatus, a sleeve-like printing forme can be produced both with a variable diameter and with a variable length or printing width.
With the apparatus, it is therefore possible to produce a variable-format sleeve-like printing forme.
Other objects and features of the present invention will become apparent from the following detailed description considered in conjunction with the accompanying drawings. It is to be understood, however, that the drawings are designed solely for purposes of illustration and not as a definition of the limits of the invention, for which reference should be made to the appended claims. It should be further understood that the drawings are not necessarily drawn to scale and that, unless otherwise indicated, they are merely intended to conceptually illustrate the structures and procedures described herein.